
body,html{
    margin:0;
      padding:0;

}
#main{
    margin:20px auto;
      width:260px;

}
#calc{
    margin-left:52px;
      width:60px;

}
input{
    margin:5px 0;

}
span{
  color:red;
  margin-left:5px;
}
#kuan{
  color:red;
}
#gao{
  color:red;
}
